Taken in isolation, it's a simple repudiation, a gnomic claim to be God, or an invitation to consider more closely how Jesus is special but not God. Hard to say without more context.
The closest that the Gospel of Mark comes to indicating its christology might be the baptism scene:
10 And when he came up out of the water, immediately he saw the heavens being torn open and the Spirit descending on him like a dove. 11 And a voice came from heaven, “You are my beloved Son; with you I am well pleased.”
If the Spirit descends on Jesus, then it doesn't seem like Jesus himself was the Nicene Creed God ("born of the Father before all ages. God from God, Light from Light, true God from true God, begotten, not made, consubstantial with the Father; through him all things were made") or Chalcedonian Creed God ("the same perfect in Godhead and also perfect in manhood; truly God and truly man, of a reasonable soul and body; consubstantial with us according to the manhood; in all things like unto us, without sin; begotten before all ages of the Father according to the Godhead, and in these latter days, for us and for our salvation, born of the virgin Mary").
Negative evidence may be perceived also from the trial scene (Mark 14):
55 The chief priests and the whole Sanhedrin were looking for evidence against Jesus so that they could put him to death, but they did not find any. 56 Many testified falsely against him, but their statements did not agree.
57 Then some stood up and gave this false testimony against him: 58 “We heard him say, ‘I will destroy this temple made with human hands and in three days will build another, not made with hands.’” 59 Yet even then their testimony did not agree.
60 Then the high priest stood up before them and asked Jesus, “Are you not going to answer? What is this testimony that these men are bringing against you?” 61 But Jesus remained silent and gave no answer.
Again the high priest asked him, “Are you the Messiah, the Son of the Blessed One?”
62 “I am,” said Jesus. “And you will see the Son of Man sitting at the right hand of the Mighty One and coming on the clouds of heaven.”
63 The high priest tore his clothes. “Why do we need any more witnesses?” he asked. 64 “You have heard the blasphemy. What do you think?”
They all condemned him as worthy of death. 65 Then some began to spit at him; they blindfolded him, struck him with their fists, and said, “Prophesy!” And the guards took him and beat him.
Notably absent is any charge that Jesus claimed to be God.
That would have been the most obvious charge of blasphemy, and it is used in John.
The emphasis on the disagreement of the witnesses and false testimony suggests that the charges were invalid; that it was not blasphemy.
The invalidity of the accusations in Mark is also suggested by Pilate's judgment of them:
9 “Do you want me to release to you the king of the Jews?” asked Pilate, 10 knowing it was out of self-interest that the chief priests had handed Jesus over to him.
A similar scene to Mark 10:17-18 appears in Mark 2:
5 When Jesus saw their faith, he said to the paralyzed man, “Son, your sins are forgiven.”
6 Now some teachers of the law were sitting there, thinking to themselves, 7 “Why does this fellow talk like that? He’s blaspheming! Who can forgive sins but God alone?”
8 Immediately Jesus knew in his spirit that this was what they were thinking in their hearts, and he said to them, “Why are you thinking these things? 9 Which is easier: to say to this paralyzed man, ‘Your sins are forgiven,’ or to say, ‘Get up, take your mat and walk’? 10 But I want you to know that the Son of Man has authority on earth to forgive sins.” So he said to the man, 11 “I tell you, get up, take your mat and go home.” 12 He got up, took his mat and walked out in full view of them all. This amazed everyone and they praised God, saying, “We have never seen anything like this!”
The claim there is that "the Son of Man has authority on earth," which would be given by God, even though he is not God.
(Matthew 16:19 is another interesting verse showing how a man could be given authority that would otherwise be a divine prerogative.)